Brief Answer:
likely anemia. Get ekg done

Detailed Answer:
Thank you for asking

I read your question and I understand your concern. With sudden out of sleep palpitations and history of anemia and low folate and high reticulocytes the likely explanation for these palpitations is anemia. Also sleep and wake transition in morning and sudden standing up or sitting in the bed from lying down also gives palpitations due to epinephrine surge .

High potassium however should be evaluated and if palpitations are still there get an ekg done to be on the safer road. If that comes clean then no worries. All you would need is some folate supplements and diet rich in folates like green leafy vegetables beans and lentils etc.

I hope it helps. Take good care of yourself and don't forget to close the discussion please.

Regards XXXXXXX

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